As someone who crossed the finish line in Boston, Hill said it was surreal to watch the violence that occurred on Monday.

"It was unbelievable to see it unfolding," he said. "To think someone would do that is unimaginable."

In the middle of the eighth inning at Marlins Park, the Marlins' in-game host, Katherine, was on the video scoreboard asking the crowd of 16,200 to rise and sing "Sweet Caroline" in tribute to the victims in Boston. One fan was shown holding a USA flag with wording to pay tribute to the victims in Boston.

The tragedy in Boston raises awareness of security at all public events, including baseball stadiums like Marlins Park.

"You always have to be mindful and be careful with everything you do," Hill said. "Hopefully, this was just a sick person or sick people who will be brought to justice, and it won't happen again. You always have to be mindful and aware of your surroundings to what is going on."